Fix retry mechanism to raise when it fails to checkout.

TBR=jochen
BUG=
TEST=

Review URL: http://codereview.chromium.org/4132002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@63832 0039d316-1c4b-4281-b951-d872f2087c98

scm.py

@@ -351,7 +351,9 @@ class SVN(object):
     compiled_pattern = re.compile(pattern)
     # Place an upper limit.
     backoff_time = 5
-    for _ in range(10):
+    i = 0
+    while True:
+      i += 1
       previous_list_len = len(file_list)
       failure = []
 
@@ -404,6 +406,8 @@ class SVN(object):
           if len(file_list) == previous_list_len and not IsKnownFailure():
             # No known svn error was found and no progress, bail out.
             raise
+        if i == 10:
+          raise
         print "Sleeping %.1f seconds and retrying...." % backoff_time
         time.sleep(backoff_time)
         backoff_time *= 1.3